rs200716018
Variant summary
Our verdict is Likely benign. Variant got -3 ACMG points: 0P and 3B. BP4_ModerateBP6
The NM_001267550.2(TTN):āc.106442A>Gā(p.Lys35481Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000161 in 1,611,666 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_001267550.2 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -3 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
TTN | NM_001267550.2 | c.106442A>G | p.Lys35481Arg | missense_variant | Exon 359 of 363 | ENST00000589042.5 | NP_001254479.2 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
TTN | ENST00000589042.5 | c.106442A>G | p.Lys35481Arg | missense_variant | Exon 359 of 363 | 5 | NM_001267550.2 | ENSP00000467141.1 |
Frequencies
GnomAD3 genomes AF: 0.000105 AC: 16AN: 152196Hom.: 0 Cov.: 33
GnomAD3 exomes AF: 0.0000405 AC: 10AN: 247170Hom.: 0 AF XY: 0.0000373 AC XY: 5AN XY: 134010
GnomAD4 exome AF: 0.000166 AC: 243AN: 1459470Hom.: 0 Cov.: 32 AF XY: 0.000152 AC XY: 110AN XY: 725848
GnomAD4 genome AF: 0.000105 AC: 16AN: 152196Hom.: 0 Cov.: 33 AF XY: 0.0000941 AC XY: 7AN XY: 74356
ClinVar
Submissions by phenotype
not provided Uncertain:3Benign:1
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The TTN c.106442A>G; p.Lys35481Arg variant (rs200716018; ClinVar Variation ID: 284002) is rare in the general population (<0.2% allele frequency in the Genome Aggregation Database) and has been reported in one individual with dilated cardiomyopathy (Mazzarotto 2020). The clinical relevance of rare missense variants in this gene, which are identified on average once per individual sequenced in affected populations (Herman 2012), is not well understood. Yet, evidence suggests that the vast majority of such missense variants do not contribute to the clinical outcome of DCM (Begay 2015). Thus, the clinical significance of the p.Lys35481Arg variant cannot be determined with certainty. References: Begay RL et al. Role of Titin Missense Variants in Dilated Cardiomyopathy. J Am Heart Assoc. 2015 Nov 13;4(11). PMID: 26567375. Herman DS et al. Truncations of titin causing dilated cardiomyopathy. N Engl J Med. 2012 Feb 16;366(7):619-28. PMID: 22335739. Linke WA and Hamdani N. Gigantic business: titin properties and function through thick and thin. Circ Res 2014; 114(6): 1052-1068. PMID: 24625729. Mazzarotto F et al. Reevaluating the Genetic Contribution of Monogenic Dilated Cardiomyopathy. Circulation. 2020 Feb 4;141(5):387-398. PMID: 31983221. -
This variant is associated with the following publications: (PMID: 31983221) -
not specified Uncertain:1
Variant summary: TTN c.98738A>G (p.Lys32913Arg) results in a conservative amino acid change located in the M-band domain of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4e-05 in 247170 control chromosomes. To our knowledge, no occurrence of c.98738A>G in individuals affected with Limb-Girdle Muscular Dystrophy, Type 2J and no experimental evidence demonstrating its impact on protein function have been reported. Eight submitters have cited clinical-significance assessments for this variant to ClinVar after 2014, classifying the variant as uncertain significance (n=5) or likely benign (n=1). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
TTN-related disorder Uncertain:1
The TTN c.106442A>G variant is predicted to result in the amino acid substitution p.Lys35481Arg. This variant was reported in an individual with dilated cardiomyopathy (Table S3, Mazzarotto et al. 2020. PubMed ID: 31983221). This variant is reported in 0.0083% of alleles in individuals of African descent in gnomAD (http://gnomad.broadinstitute.org/variant/2-179394776-T-C). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
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Cardiomyopathy Uncertain:1
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Dilated cardiomyopathy 1G Uncertain:1
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Early-onset myopathy with fatal cardiomyopathy Uncertain:1
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Cardiovascular phenotype Uncertain:1
The p.K26416R variant (also known as c.79247A>G), located in coding exon 186 of the TTN gene, results from an A to G substitution at nucleotide position 79247. The lysine at codon 26416 is replaced by arginine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be benign by PolyPhen in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Tibial muscular dystrophy Benign:1
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Myopathy, myofibrillar, 9, with early respiratory failure Benign:1
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at